Today's agricultural equipment including mobile harvesting machines, such as combines and the like, are aesthetically designed without detracting from their usefulness. To effect such ends, an engine for such harvesting machines is usually enclosed in a walled structure. Also mounted within the walled structure is a heat exchanger, such as a radiator, for cooling the engine. An engine driven fan is provided to draw a large volume of environmental air across the radiator in heat exchanging relationship therewith.
Combines and the like are typically operated in extremely dirty and dusty conditions. Accordingly, it is conventional to provide screens or filters for removing relatively large pieces of foreign material, such as chaff and leaves, from the air drawn toward the radiator. Since the combine is working in a dirty environment, keeping the screen or filter clean has presented a serious problem.
Various solutions to the problem have been proposed One type of well known filtering system features the use of an apertured rotary screen with baffles. The baffles are arranged adjacent an interior side of the screen to blank off a section of the screen as the screen rotates. The baffles effectively cut off the inward air flow in the area of the screen opposite the baffle so that the trash or foreign material drawn against the baffled screen area is allowed to fall off the screen.
The above system, however, has not been totally satisfactorily in eliminating the problem of foreign materials in the environmental air drawn toward the radiator. Openings in the screen must be sized large enough to allow a large volume of air to be drawn into heat exchanging relation with the radiator. The size of such openings, however, also allows dirt and other foreign material to pass through the screen and be deposited upon a front face of the radiator or heat exchanger core.
As will be understood, an accumulation of foreign material on a front face of the radiator core ultimately causes blockage or plugging of air flow through the radiator. Depending upon harvesting conditions, the operator may have to frequently stop to clean the radiator core so as to prevent overheating of the engine. In some conditions, blockage or plugging of the radiator core occurs in a relatively short time adding frustration and valuable time to the harvesting operation.
The specific orientation of the radiator within a machine can affect the above debris accumulation. Specifically, some engine configurations require positioning of the radiator so that cooling air is forced to change direction in its flow path toward the radiator. The effects of inertia on debris thus results in more pronounced accumulation at the downstream most portion of the radiator.
In view of the above, it would be desirable to have an air intake system for an agricultural implement wherein the interval between radiator core cleaning operations could be extended to allow the machine to be used to its optimum capacity.